The Great White Dragon is rarely seen. Nobody knows where he slumbers, but they do know his cave is on one of the highest peaks in the world. Only few stories have made it to be Known about across the lands. Few ever made it back to there home villages to tell the story.
One of the standard peices of equipment for an adventurer is a sword. But swords were actually very complicated to manufacture. Therefore, an adventurer who owned a sword might have had it passed down through the generations or might have been rewarded by some influential figure. Or simply looted it from a tomb.